As a tire that can run for a certain distance even when the internal pressure of the tire decreases due to a puncture or the like, a side-reinforced run-flat tire in which a side reinforcing rubber layer crescent in cross section is provided in each sidewall portion has been conventionally available. Such a run-flat tire normally supports the load by the internal pressure of the tire and, when the internal pressure decreases, supports the load by the side reinforcing rubber layer instead.
Regarding the run-flat tire, the following technique for achieving both run-flat durability and tire weight reduction has been proposed: a crown portion of a carcass extending between a pair of bead portions is partially hollowed out to form a pair of divided carcasses (for example, see Patent Literature (PTL) 1).